Bad after sales service.

We were booked on for Mango flight for 26 September from CPT to JHB. My dad died on the 21 September. I have been phoning Mango Airline non stop. Two separate people told me to get a doctor's certificate, stating that my family and I are now in quarantine. I got the letter and emailed it through to them, with reference number : TLWBXB. I am still awaiting a reply. When I phone their call center, they keep me on hold for 45 minutes to 1 hour , after which I have still not spoken to any representative.